I apologize if there is already a thread on this. I am interested in how much electricity is lost in the charging process. If you pump 85 KWH into your battery, I am sure that your electric meter on your house will show that you used more than 85 KWH. My question is how much more. All of Tesla's analysis assumes that there is no loss - i.e. perfect transfer - from the AC current in your house into the DC battery in the Model S. Does anyone know how much that loss is and are there any factors that impact that loss - e.g. temperature, current level... And is there anyway to measure the loss. It seems to me that knowing that is critical to being able to calculate cost per mile.